1. Field of the Invention
This invention relates to alignment of optical devices. More particularly this invention relates to a technique for the axial alignment of the end face of an array of optical fibers with an edge of a support block.
2. Description of the Related Art
In the past, the assembly and manufacture of optical assemblies having a linear array of optical elements has been time consuming and prone to quality control problems. The latest developments in optical cross-connect assemblies have only magnified these problems. Precisely engineered optical receiver arrays are required in these devices. A general demand for more precisely constructed assemblies having greater reliability has translated into a demand for better manufacturing apparatuses and processes.
Optical devices of the type addressed by the present invention currently in use involve an array of optical fibers having light transmitted therethrough. In typical devices the light exiting the end faces of the fibers is transmitted through a plurality of waveguides, which produce a diffraction pattern. The diffracted light is collimated by focusing optics, and then falls on a detector array.
In current devices, it is required to precisely position an assembly of micro-lenses close to the end faces of an optical fiber array.
It is therefore a primary object of some aspects of the present invention to provide an improved technique for attaching the end of an optical fiber array to a glass block, such that the end faces of the block and the array are in precise alignment.
It is another object of some aspects of the present invention to attach an array of microlenses in precise alignment with corresponding members of an optical fiber array.
The invention provides a method for aligning two blocks, including the steps of placing an end face of a first block in a first face-to-face contacting position against a planar wall, laterally stabilizing the first block in the first face-to-face contacting position, and disposing the bottom surface of a second block in a second face-to-face contacting position with the top surface of the first block, wherein an end face of the second block is in a third face-to-face contacting position with the wall. The method further includes applying pressure against the top surface of the second block while maintaining the second face-to-face contacting position, wherein the pressure is distributed substantially over the top surface of the second block. The method further includes, while applying the pressure, adhering the bottom surface of the second block to the top surface of the first block.
According to an aspect of the method, the pressure is applied by disposing a third block on the top surface of the second block, and applying the pressure to the third block. The third block can be a Delarin block.
Another aspect of the method includes applying an adhesive to the bottom surface of the second block prior to disposing the bottom surface of the second block on the top surface of the first block, and curing the adhesive. The adhesive can be UV glue or an epoxy glue.
According to an additional aspect of the method, the wall has a lower segment and an upper segment that is offset from the lower segment, wherein in the first face-to-face contacting position the end face of the first block contacts the lower segment, and in the second face-to-face contacting position the end face of the second block contacts the upper segment.
According to one aspect of the method, the second block includes an array of optical fibers.
Another aspect of the method includes disposing an array of microlenses on the second block proximate an outlet of the array of optical fibers.
According to a further aspect of the method, the wall includes a first pin and a second pin that is spaced apart from the first pin.
The invention provides a method for aligning an array of optical elements on a block, including the steps of placing an end face of a first block in a first face-to-face contacting position against a planar wall, laterally stabilizing the first block in the first face-to-face contacting position, disposing the bottom surface of a fiberoptic array in a second face-to-face contacting position with a top surface of the first block, wherein an end face of the fiberoptic array is in a third face-to-face contacting position with the wall. The method includes applying pressure against the top surface of the fiberoptic array, while maintaining the second face-to-face contacting position, wherein the pressure is distributed substantially over the top surface of the fiberoptic array, and while applying the pressure, adhering the bottom surface of the fiberoptic array to the top surface of the first block.
According to an aspect of the method, the pressure is applied by disposing a third block on the top surface of the fiberoptic array, and applying the pressure to the third block. The third block may be a Delarin block.
Another aspect of the method includes applying an adhesive to the bottom surface of the fiberoptic array prior to disposing the bottom surface of the fiberoptic array and curing the adhesive. The adhesive may be UV glue or epoxy glue.
According to still another aspect of the method, the wall includes a lower segment and an upper segment that is offset from the lower segment, wherein in the first face-to-face contacting position the end face of the first block contacts the lower segment, and in the second face-to-face contacting position the end face of the fiberoptic array contacts the upper segment.
An additional aspect of the method includes disposing an array of microlenses on the fiberoptic array proximate the end face of the fiberoptic array.
According to one aspect of the method, the wall includes a first pin and a second pin that is spaced apart from the first pin.
The invention provides an apparatus for aligning an optical array, including a receiving section that accepts a first block and an array of optical elements, wherein the array of optical elements includes a second block. The apparatus further includes a retaining section adjacent the receiving section for stabilizing the first block in an operating position, wherein the retaining section includes a platform that carries the first block thereon. The apparatus further includes an upright frame, which has an extension that overhangs the platform, and has a wall that abuts the first block and the second block during alignment thereof. The apparatus further includes a plurality of horizontally directed stabilizers mounted on the retaining section that urge the first block into a first face-to-face contacting position with a lower segment of the wall, and a vertically directed stabilizer mounted on the extension that holds a bottom surface of the second block in face-to-face contact with a top surface of the first block and holds an end face of the second block in a second face-to-face contacting position with an upper segment of the wall.
According to an aspect of the apparatus, the horizontally directed stabilizers each comprise an upright stub having a hole bored therethrough, and a pin inserted through the hole. The pin may be a bolt threaded through the hole.
According to yet another aspect of the apparatus, the vertically directed stabilizer includes a pin inserted through a bore that is formed in the extension. The pin can be a bolt threaded through the bore.
According to still another aspect of the apparatus, the wall includes two upright posts and a gap therebetween.
According to an additional aspect of the apparatus, the lower segment of the wall includes a niche, the end face of which is offset from the upper segment of the wall.
One aspect of the apparatus the lower segment of the wall includes an outstanding step that is offset from the upper segment of the wall.
According to a further aspect of the apparatus, a width dimension of the extension is less than a width dimension of the platform.
The invention provides an apparatus for aligning an optical array, including a receiving section that accepts a first block, and an array of optical elements, wherein the array of optical elements includes a second block. The apparatus further includes a retaining section adjacent the receiving section for stabilizing the first block in an operating position, wherein the retaining section includes a platform for carrying the first block thereon. The apparatus further includes an upright frame having an extension that overhangs the platform, wherein the width dimension of the extension is less than the width dimension of the platform. The apparatus further includes a wall that abuts the first block and the second block during alignment thereof, a plurality of horizontally directed stabilizers mounted on the retaining section that urge the first block into a first face-to-face contacting position with a lower segment of the wall. The horizontally directed stabilizers each comprise an upright stub that has a hole bored therethrough and a first bolt threaded through the hole, and a vertically directed stabilizer mounted on the extension that holds a bottom surface of the second block in face-to-face contact with a top surface of the first block, and holds an end face of the second block in a second face-to-face contacting position with an upper segment of the wall, wherein the vertically directed stabilizer includes a second bolt threaded through a bore that is formed in the extension.
According to an aspect of the apparatus, the wall includes two upright posts an a gap therebetween.
According to an additional aspect of the apparatus, the lower segment of the wall includes a niche that is offset from the upper segment of the wall.
One aspect of the apparatus the lower segment of the wall includes an outstanding step that is offset from the upper segment of the wall.